PowerPoint was originally designed to make it easier to prepare actual overhead transparencies, actual 35mm slides. PowerPoint 1.0 (for Mac, April 1987) produced overhead transparencies on a black-and-white Macintosh for laser printing, removing the need to manually re-type the slide.

PowerPoint’s first features came from analysing real slides to find out what the user needed: “55% of the overheads contained bulleted lists, about 70% of the overheads contained diagrams, and about 35% of the overheads combined both”

Master slide was originally called “Model Slide”

The correct way to write PPT is “PowerPoint”. Use of the extra internal upper-case letter was mandatory for Mac software, based on Apple’sstyle in product naming.